Border wires are commonly used with spring cushion products, such as mattress innerspring assemblies. A plurality of coil springs are arranged to form a support area for the mattress, with the coil springs joined together into a unit, such as by crosshelical springs extending across the length and width of the mattress. A border wire extends around a perimeter meter defined by the coil springs along the outside of the support area. The border wire fixes the edge of the innerspring assembly and provides an extra degree of firmness around the innerspring perimeter.
In large innerspring units, such as those used in king-size mattresses, the border wire is formed in two U-shaped pieces. The U-shaped pieces meet or abut one another along portions of the border wire at the ends of each U that are bent inwardly (i.e. into the mattress). The inwardly extending abutting portions are typically joined together by helical coils, for example. This permits the border wire sections to rotate with respect to each other. The large innerspring can thus be folded to pass through small areas such as doors, stairways, elevators and the like.